What are the three coats of a traditional cement plaster system?

What are the three coats of a traditional cement plaster system?

• A. Scratch coat, brown coat, and finish coat
• B. Base coat, scratch coat, and finish coat
• C. Scratch coat, finish coat, and primer
• D. Brown coat, finish coat, and top coat

Answer: (A)

In a traditional cement plaster system, the wall is built up in three coats with specific roles. The first coat, the scratch coat, is applied to the lath and then scratched to create a rough key for the next layer. The second coat, the brown coat, adds bulk and levels the surface to the desired thickness. The final layer, the finish coat, is a thin top coat that delivers the smooth, decorative surface ready for painting or other finishes. This sequencing matches the standard terminology and practice. A primer is not part of the plaster layering itself, and a base coat or top coat are not the conventional terms used for the three-layer cement plaster system—the recognized trio is scratch coat, brown coat, and finish coat.

In a traditional cement plaster system, the wall is built up in three coats with specific roles. The first coat, the scratch coat, is applied to the lath and then scratched to create a rough key for the next layer. The second coat, the brown coat, adds bulk and levels the surface to the desired thickness. The final layer, the finish coat, is a thin top coat that delivers the smooth, decorative surface ready for painting or other finishes.

This sequencing matches the standard terminology and practice. A primer is not part of the plaster layering itself, and a base coat or top coat are not the conventional terms used for the three-layer cement plaster system—the recognized trio is scratch coat, brown coat, and finish coat.